If you have access DirectX library you may use IStream to convert your image to JPEG http://msdn.microsoft.com/en-us/library/windows/desktop/aa380034(v=vs.85).aspx
or if you have GDI+ something like this might work
Gdiplus::Bitmap bmp(hbmpImage,(HPALETTE)0);
CLSID pngClsid;
GetEncoderClsid(L"image/png", &pngClsid);
bmp.Save(L"D:\image.png",&pngClsid,NULL);
where GetEncoderLCLsid looks like this:
int GetEncoderClsid(const WCHAR* format, CLSID* pClsid)
{
UINT num = 0; // number of image encoders
UINT size = 0; // size of the image encoder array in bytes
ImageCodecInfo* pImageCodecInfo = NULL;
GetImageEncodersSize(&num, &size);
if(size == 0)
return -1; // Failure
pImageCodecInfo = (ImageCodecInfo*)(malloc(size));
if(pImageCodecInfo == NULL)
return -1; // Failure
GetImageEncoders(num, size, pImageCodecInfo);
for(UINT j = 0; j < num; ++j)
{
if( wcscmp(pImageCodecInfo[j].MimeType, format) == 0 )
{
*pClsid = pImageCodecInfo[j].Clsid;
free(pImageCodecInfo);
return j; // Success
}
}
free(pImageCodecInfo);
return -1; // Failure
}
don't forget to initialize GDI+
GdiplusStartupInput gdiplusStartupInput;
ULONG_PTR gdiplusToken;
GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);
if don't have access to either you may use libjpeg but you need to put all the dependencies packages from the GnuWin32 site. Much faster the code in this page should work, just forget about the boost